Variable radius fillet for cylindrical object

Hi All,

        i am trying to add variable radius fillet for a cylinder as shown in the pic attached. since it is continuos, we do not have a vertex to specify the radius value. i tried by adding reference points before using fillet command, but i am not able to choose those points while the Variable fillet command is active. Am i using the tool correctly or am i missing something?

        How can this be done?

Thanks and Regards,

Prashanth.P

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